1. Field of the Invention
The present invention relates to an aligner elevation apparatus for an integrated circuit handler. More particularly, the present invention is directed to an aligner elevation apparatus, wherein the apparatus is operated to raise an aligner of an integrated circuit exchanger through the use of a single driving motor when the integrated circuit devices are loaded/unloaded into/from a test site, and then operated to accurately place the integrated circuit devices in carrier modules of test trays, and not damage the devices.
2. Prior Art
Manufactured integrated circuit devices are transferred using a horizontal or vertical-type elevator and then sequentially deposited in a plurality of carriers mounted on test trays, for testing of the devices.
The devices that are sequentially deposited in the test trays are supplied to a heating chamber that has been set to a predetermined temperature suitable for the performance of the tests of the devices, and are then heated to a higher temperature, followed by electrical contact with a testing section in a test site and the performance of tests on the devices.
The devices that have been tested according to the above procedures are subsequently classified into different classifications, depending upon the test results. The classified devices are put in the test trays associated with the individual classifications. The sorted devices are then further classified into a passed or failed category, based upon error detection by the testing equipment. The passed devices are available as the final products, and the failed devices are discarded.
The devices supplied from the elevator in a loading section are put in the test trays and then elevated. When the test tray reaches a maximum raised position of the elevator, a tray transferring unit is moved upward in order to capture the elevated trays and to then position them into respective loading sections.
Meanwhile, each of he devices, contained in the trays having been moved by the tray transferring unit, is held by vacuum from a picker, which moves the held device into the heating chamber, during which the alignment of the device is made.
The alignment of the device includes, after the picker engages each device by a vacuum nozzle, depositing the device into a buffer, then vacuum engaging each device by the picker from the buffer and supplying it to an exchanger. The exchanger is provided with an aligner for accurately placing the device that has been moved by the picker, in place. Subsequent to an elevating operation of the aligner, the positioning of the device is made.
Such an elevating operation of the aligner serves two functions, providing positional stability of the device in the test tray and accurate placement of the device therein. To this end, the elevating operation consists of a long-up operation where a body of the exchanger is raised, and a short-up operation where the aligner of the exchanger is raised to accurately seat the device.
The vertical displacement motions in the long-up and short-up operations are respectively made by two pairs of pneumatic cylinders, each pair being installed in the exchanger. Specifically, the operation of one of the two pairs of cylinders, installed in both sides of the exchanger, permits a stroke movement of the body of the exchanger, so that the body reaches a predetermined position. Thereafter, the other two cylinders again raise the aligner, which aligner accurately deposits the device, that is seated on the top portion of the aligner, in the test tray.
However, the above-mentioned long-up and short-up operations accompanies an occurrence of loud noise, as well as unwanted damage of the device. Further, in the case of employing two pairs of cylinders, the operation depends on the stroke of the cylinders, which operation causes deviation or breakage of the devices during the short-up operation, thus increasing the failure rate of the devices.
An elevation apparatus for a handler used for loading/unloading integrated circuit devices into/from a test tray is provided The apparatus includes an up/down block slidably mounted to be vertically displaceable with respect to a base plate. A nozzle block is affixed to the up/down block for displacement therewith. The nozzle block carries a plurality of nozzles respectively coupled to a vacuum source. An aligner assembly is disposed above the nozzle block and supported by a pair of upper base blocks that are slidably mounted for displacement relative to the base plate. An elastically coupling assembly couples the pair of upper base blocks to the up/down block, the elastic coupling assembly upwardly displacing the pair of upper base blocks responsive to a corresponding upward displacement of the up/down block. The apparatus also includes a drive assembly secured to the base plate and coupled to the up/down block for vertically displacing the up/down block. The drive assembly is driven to first provide a long-up operation, where the up/down block is displaced to displace the aligner assembly into contact with a test tray and provide support thereof. The drive assembly is secondly driven to provide a short-up operation, where the up/down block is displaced to displace the test tray into contact with a plurality of supporting jaws. Then, the drive assembly is thirdly driven to displace the up/down block to now displace the nozzle block into contact with the aligner assembly, while the displacement of the aligner assembly is blocked by the contact between the test tray and the supporting jaws. The elastic coupling assembly elastically compensates for the third displacement of the up/down block. Thus, a single driving device, such as a motor driven ball screw, is used for all three of the aforementioned displacement steps, without requiring the use of pneumatic or hydraulic cylinders, or other linear displacement devices for the final positioning of the nozzle assembly. By that arrangement, the equipment can be made smaller and damage to the integrated circuit devices can be prevented.